Method of forming and filling containers at high rates of speed

ABSTRACT

The method of thermoforming and filling containers while operating both forming and filling equipment at optimum speeds. This is accomplished by taking a wide sheet or web of plastic and forming a substantial number of transversely spaced containers. The stroke, or forward motion of the sheet, is kept as short as practical, thus minimizing any heat loss in the plastic sheet while it moves from the heating station to the forming station. After forming, portions of the plastic sheet containing the formed containers-or the containers themselves-are severed from the main web and moved off at an angle relative to the longitudinal direction movement of the main web to filling stations, where filling can take place at the desired rate. With this system, there can be utilized the advantages of efficient forming, and of rapid filling.

United States Patent [72] Inventor Seymour C. Graham 330 W. Diversey, Chicago, Ill. 60657 {2 l] Appl. No. 844,313

[22] Filed July 24, 1969 [45] Patented Dec. 21, 1971 [54] METHOD OF FORMING AND FILLING CONTAINERS AT HIGH RATES OF SPEED 3,530,636 9/1970 Weprin etal.

ABSTRACT: The method of thermoforming and filling containers while operating both forming and filling equipment at optimum speeds. This is accomplished by taking a wide sheet or web of plastic and forming a substantial number of transversely spaced containers. The stroke, or forward motion of the sheet, is kept as short as practical, thus minimizing any heat loss in the plastic sheet while it moves from the heating station to the forming station. After forming, portions of the plastic sheet containing the formed containers-or the containers themselves-are severed from the main web and moved off at an angle relative to the longitudinal direction movement of the main web to filling stations, where filling can take place at the desired rate. With this system, there can be utilized the advantages of efficient forming. and of rapid filling.

METHOD OF FORMING AND FILLING CONTAINERS AT HIGH RATES OF SPEED In conventional form-seal operations, the heating, forming, and filling mechanisms are built in-line. That is to say that they are designed to follow one after another in a longitudinal direction, with the result that the limitations of the heating and forming cycle determine the number of units that can be acted on at any given time and within a particular time interval by the filling equipment. Thus, the time utilized in forming is a limiting factor on the number of containers that are filled, unless the sheet be unduly wide; and to feed a wide sheet into the filler requires expensive and costly filling mechanism, which would then operate at well below potential.

Further, an in-line former and filler normally strokes, or cycles, concurrently at each station, which means that for each forming stroke there is a filling stroke and a capping stroke. To break this relationship, requires complex and costly mechanism, which is frequently difiicult to operate. These inherent disadvantages in presently existing form-seal equipment result in slow speed and low output in relation to dollar investment.

In accordance with the present invention, there is provided a novel system wherein the forming equipment and the filling equipment can each be used in a manner which provides for the greatest efficiency of that particular component. The forming and filling portions of the systems are integrated with either a common power source, or with separate power sources that are interrelated and synchronized so that the speed of one portion is adjusted to the speed of the other.

To accomplish the advantages of this invention, a wide heating and forming unit is used, which permits the formation of a substantial number of containers within the single short stroke necessitated by the limited movement that can be allowed to take place between the heater and the forming equipment.

When practicing the present invention, the containers formed by the forming equipment are moved off at an angle relative to the forming equipment and in a position and relation that provides for maximum filling efficiency. The containers may, of course, (I) be a part of a section severed from the main web, or (2) be separated from the web. In the latter situation, if desired, the portion of the web remaining after the containers have been removed can be conveyed in its original direction to waste. Suitable mechanisms can be provided for separating the formed containers from the plastic sheet and for ensuring proper directional movement thereof. Any of a variety of mechanisms can be employed and they do not form a part of the present invention. In view of the fact that the containers and interconnected material, or containers themselves severed from the web, can be moved at a speed and pace or rhythm determined by a suitably provided conveyor system, the containers can be moved beneath a plurality of longitudinally and transversely spaced filling nozzles in a way most efficient for this specific operation. The movement of these formed containers through the filler and capper, at an angle from the longitudinal movement of the web being formed and completely separated therefrom, permits the continuation of the thermoforming to take place without impediment. If greater filling speed is desired, a wider sheet is fed through the former, thus producing more containers per stroke; but the length of stroke and the frequency of stroke are maintained at maximum efficiency for the forming operation.

The handling of the containers can be facilitated by slotting or. registering the plastic while it is being formed, using holes or other registering devices. The formed sheet can be properly conveyed and registered on the filling apparatus, so that it is properly stationed for filling and capping, or other types of closing.

An additional obvious advantage of this method is that if the forming machine malfunctions during operation, the improperly formed plastic can be easily removed from the production line and need not be fed to succeeding stations, thus causing misalignment. The plastic need merely be fed through the forming cycle, after which it can readily be taken off the line and scrapped.

As an example of what can be accomplished by this invention, assume that you have available filling machines that operate at 60 to strokes per minute. If three filling nozzles are used, the filling machines are capable of filling -270 containers per minute. It is obvious that in a straight in-line relation between the forming equipment and filling nozzles, the forming equipment would not produce containers this fast, since the conventional forming equipment operates at a rate of between 10 and 30 strokes per minute. However, with the present invention, you could utilize a sheet of material that is six containers wide across the forming machine and three containers wide on the stroke dimension. Thus, with forming equipment operating at 10 strokes per minute, you could form 180 containers per minute, which could be filled by three filling nozzles operating at approximately 60 strokes per minute. In this example, the strip severed from the main sheet would be as many containers in the stroke dimension as there are nozzles in the filling device, and movement of the severed strip would be determined by the speed of the filler in cycles per minute. It can clearly be seen that this arrangement provides for maximum utilization of both the forming and filling equipment.

As will be clear from the following drawings, various systems could be employed to accomplish the desired results, and other objects and advantages will be apparent therefrom, in which:

FIG. 1 shows an arrangement where the filling equipment is located at a right angle relative to the heating and forming equipment;

FIG. 2 shows a system wherein the filling station is located at less than a right angle relative to the direction of travel of the plastic web through the heating and forming station;

FIG. 3 is a schematic representation of a heating, forming and cutting station; and

FIG. 4 shows a system similar to FIG. I in which the containers have been severed from the plastic sheet and the severed web is carried to waste.

Referring first to FIG. ll, there is shown a web of plastic material 2, which is directed through a heating station, where the plastic is heated so that it can be thermoformed. The plastic leaves the heating station 4 and enters the forming station 6, where thermoforming of containers 7 takes place, either by vacuum, or pressure, or both. At that point the containers are formed in wide rows and the rows progressively form columns in the direction of movement of the sheet (see FIG. 1). After the containers have so been formed and while they are still part of the sheet, they pass through a cutting station 8 where a group of containers interconnected in a section of the sheet are severed from the balance of the sheet. This strip is relatively narrow and is made of second rows as many containers wide as there are filling nozzles.

To obtain maximum utilization of high-speed filling equipment, the direction of travel of severed section 10 is changed by moving it off at a right angle (FIG. 1), or at an angle less than a right angle (FIG. 2) to a station 18, where the filling of the rows of containers takes place.

There are schematically illustrated two filling stations for the second columns of the second rows of containers, one on opposite sides of the direction of travel of the web, and they each include a cutting and trimming station I4, scrap removal station I6, filling station 18, and capping and sealing station 20. The embodiments shown in FIGS. l and 2 are merely intended to be schematic, as other steps can be performed, either before or after the direction of the severed portions is changed relative to the longitudinal movement of the web.

For example, the term cut," as applied to station 8, can consist of three separate operations; (1) where a guillotine slice is cut off from the rest of the web, (2) a partial trimming of the plastic takes place, so that the amount of waste going through the machine is reduced, yet enough plastic is retained in the web so that the containers may be bound together when going through the plastic machine, and (3) a complete trim can take place where the containers are removed from the web and the waste web is either chopped up, or carried away, or disposed of in some fashion. Obviously, it makes no difference whether the cutting is done at a plurality of stations.

In FIG. 2, there is illustrated a system that employs a common power source for both the forming and filling mechanisms. The motor 22, through suitable gearing 24, and other conventional drive components, operates both the fonning and filling mechanisms in a prescribed synchronized relationship. While this has been illustrated with respect to the embodiment shown in FIG. 2, it obviously can also be used with the embodiment shown in FIG. 1. Additionally, while a motor and drive of one typehas been illustrated, it is, of course, within the framework of such a system to employ other components that will provide the desired relationship from a single drive motor. Also, separate motors can be employed along with suitable control mechanisms to synchronize their operation.

FIG. 4 shows a system wherein the containers 7 are completely severed from the severed section 10 and are supported on a conveyor 21 designed to receive containers 7. The severed web section 10A is then continuously moved in a 1ongitudinal direction to waste. While in the embodiment shown in this figure the forming and cutting are done at two separate stations, it is, of course, possible to sever the cups from the web in the forming station and thus do away with the separate cutting station.

Additionally, while in the described embodiment intermittent movement through the system has been described, the present invention would apply with equal vitality if the system was designed to operate continuously. It is also noted that while the two embodiments listed the forming mechanism as being disposed in a horizontal plane, it is, of course, within the scope of this invention to do the forming in a vertical plane.

It will, of course, be seen that there are many other objects and advantages of the present invention, and it is only intended to limit the protection as determined by the scope of the following claims.

lclaim:

I. A method of forming and filling containers at a rapid rate comprising the steps of conveying a continuous thermoplastic sheet of material in a longitudinal direction, heating the sheet of material, moving the sheet of material into thermoforming equipment, cyclically thermoforming in said sheet wide rows of containers having a plurality of containers in each row at a first row-forming rate as said sheet moves into and then out of said thermoforming equipment, then dividing said rows of containers into columns of containers having narrow rows each of which contains fewer containers than said wide rows of containers, moving said columns of containers through a filling station at a cycling speed substantially faster than said cyclical forming rate, and filling said narrow rows of containers at a cycling rate which is faster than said cyclical rowfonning rate.

2. The method of claim 1 wherein the'steps of moving said columns of containers is at an angle sidewise to the direction of movement of the sheet out of said thermoforming equipment.

3. The method of claim 2 wherein said filling rate is at least twice as fast as said row-forming rate.

4. The method of claim 2 in which said wide rows are divided transversely of said sheet between adjacent wide rows into severed sections whereby a said wide row becomes a column.

5. The method of claim 2 in which said containers are severed from said sheet as said sheet is divided, and wherein containers in a wide row become containers in a column.

6. The method of claim 4 in which said severed sections are moved as an entity in said sidewise direction, said severed sections then being cut to separate the containers therefrom.

7. The method of claim 2 in which said sidewise angle is a right angle.

8. The method of claim 5 in which the remaining portion of said sheet from which the containers are severed is conveyed transversely of the direction of moyement of said columns.

9. The method of claim 2 in which said columns are moved to opposite sides, each at a sidewise angle to the direction of movement of said sheet out of said thermoforming equipment, and each through a filling station.

10. A method of forming and filling containers at a rapid rate comprising the steps of conveying a plastic sheet of material in a longitudinal direction, heating the sheet of material, moving the sheet of material into and out of thermoforming equipment, cyclically thermoforming in said sheet a wide row of containers having a plurality of containers in each row, and severing said containers from said sheet, changing the direction of movement of said containers from that of the direction of movement out of said thermoforming equipment, thereafter conveying said containers through a filling station, filling said containers in rows having fewer containers than said wide row in the thermoforming equipment; cycling filling means at said filling station at a cycle per minute in excess of that of the rate of cycling of said thermoforming equipment, whereby each of the thermoforming and filling means are independently operated at their optimum speeds, and closing said containers.

11. Apparatus for forming and filling containers comprising a forming mechanism, means for conveying a plastic sheet into and out of said forming mechanism wherein rows having a plurality of containers are repeatedly formed in said plastic sheet, and on repeated operation a plurality of columns of said rows are formed, means for severing said sheet into second rows and second columns of containers, said second rows having fewer containers than said first row, a filling mechanism disposed sidewise of the direction of movement of said sheet, means for directing said second rows and columns of containers sidewise of the direction of movement of said first columns to the filling mechanism, and means for synchronously operating said forming and filling mechanisms and for cycling said filling mechanism substantially faster than said forming mechanism.

UNITED STATES PATENT nmtt CERUMQATE M CQRREUEWN 3,628,303 Dated December 21, 1971 Seymour C. Graham Patent No.

Inventofls) It is certified that error appears in the above-identified patent and that .said Letters Patent are hereby corrected as shown below:

Column 3, line 3 should read -fer'ence whether all the cutting; is done at one station, orwhether the cutting is done at a plurality of stations.--

Signed and sealed this &1d day of Way W72.

Attestfl ROBERT eo'm'scmm EDWARD MwFLEICHEmJR,

Gossioner' of Patents Attesting Officer FORM PC4050 ($0459) USCOMM-UC 60376-1 69 1 u so novnnmnn vnmnm; OHICE: was 0-3so-:34 

1. A method of forming and filling containers at a rapid rate comprising the steps of conveying a continuous thermoplastic sheet of material in a longitudinal direction, heating the sheet of material, moving the sheet of material into thermoforming equipment, cyclically thermoforming in said sheet wide rows of containers having a plurality of containers in each row at a first row-forming rate as said sheet moves into and then out of said thermoforming equipment, then dividing said rows of containers into columns of containers having narrow rows each of which contains fewer containers than said wide rows of containers, moving said columns of containers through a filling station at a cycling speed substantially faster than said cyclical forming rate, and filling said narrow rows of containers at a cycling rate which is faster than said cyclical row-forming rate.
 2. The method of claim 1 wherein the steps of moving said columns of containers is at an angle sidewise to the direction of movement of the sheet out of said thermoforming equipment.
 3. The method of claim 2 wherein said filling rate is at least twice as fast as said row-forming rate.
 4. The method of claim 2 in which said wide rows are divided transversely of said sheet between adjacent wide rows into severed sections whereby a said wide row becomes a column.
 5. The method of claim 2 in which said containers are severed from said sheet as said sheet is divided, and wherein containers in a wide row become containers in a column.
 6. The method of claim 4 in which said severed sections are moved as an entity in said sidewise direction, said severed sections then being cut to separate the containers therefrom.
 7. The method of claim 2 in which said sidewise angle is a right angle.
 8. The method of claim 5 in which the remaining portion of said sheet from which the containers are severed is conveyed transversely of the direction of movement of said columns.
 9. The method of claim 2 in which said columns are moved to opposite sides, each at a sidewise angle to the direction of movement of said sheet out of said thermoforming equipment, and each through a filling station.
 10. A method of forming and filling containers at a rapid rate comprising the steps of conveying a plastic sheet of material in a longitudinal direction, heating the sheet of material, moving the sheet of material into and out of thermoforming equipment, cyclically thermoforming in said sheet a wide row of containers having a plurality of containers in each row, and severing said containers from said sheet, changing the direction of movement of said containers from that of the direction of movement out of said thermoforming equipment, thereafter conveying said containers through a filling station, filling said containers in rows having fewer containers than said wide row in the thermoforming equipment; cycling filling means at said filling station at a cycle per minute in excess of that of the rate of cycling of said thermoforming equipment, whereby each of the thermoforming and filling means are independently operated at their optimum speeds, and closing said containers.
 11. Apparatus for forming and filling containers comprising a forming mechanism, means for conveying a plastic sheet into and out of said forming mechanism wherein rows having a plurality of containers are repeatedly formed in said plastic sheet, and on repeated operation a plurality of columns of said rows are formed, means for severing said sheet into second rows and second columns of containers, said second rows having fewer containers than said first row, a filling mechanism disposed sidewise of the direction of movement of said sheet, means for directing said second rows and columns of containers sidewise of the direction of movement of said first columns to the filling mechanism, and means for synchronously operating said forming and filling mechanisms and For cycling said filling mechanism substantially faster than said forming mechanism. 